Project description:We isolated an efficient doxycycline degrading strain Chryseobacterium sp. WX1. To investigate gene expression patterns during doxycyclinedegradation by strain WX1, we conducted a comparative transcriptomic analysis using cultures of strain WX1 with and without doxycycline addition. The RNA-Seq data revealed that 90.44-96.56% of the reads mapped to the genome of Chryseobacterium sp. WX1 across all samples. Differentially expressed genes (DEGs) analysis (|log2FC| >2; p < 0.01) showed that 693 genes were significantly up-regulated and 592 genes were significantly down-regulated.
Project description:In this study, we isolated a potent doxycycline-degrading bacterium, Chryseobacterium sp. WX1, from environmental samples. To elucidate the molecular mechanisms underlying doxycycline degradation by strain WX1, we assessed and interpreted the proteomic profiles of Chryseobacterium sp. WX1 under conditions both with and without doxycycline exposure.
Project description:Polycomb 2 protein (PC2), a component of polycomb repressive complex 1 (PRC1), plays important roles in the maintenance of cell identity and organ development through epigenetic silencing. However, whether PC2 regulates the homeostasis of human stem cells remains unclear. Here, we demonstrate that PC2 counteracts human mesenchymal stem cell (hMSC) aging via the maintenance of nucleolar homeostasis. PC2 protein is decreased in aged hMSCs, and targeted PC2 knockout in young hMSCs results in destabilized nucleolar heterochromatin, increased ribosome biogenesis and protein translation, and accelerated cellular senescence. PC2 maintains nucleolar homeostasis by recruiting nucleolar protein fibrillarin and heterochromatin organization associated protein KAP1 at nucleolar rDNA, limiting the excessive expression of rRNAs. Importantly, overexpression of PC2 alleviates physiological hMSC aging and attenuates the development of posttraumatic osteoarthritis in mice. Taken together, our findings reveal a novel role of PC2 in counteracting senescence by maintaining nucleolar homeostasis, providing a potential therapeutic target for aging-associated disorders.